In certain industrial process plants, as for example, in steam generating plants, it often becomes necessary to cut out and replace sections or panels of a boiler tube-wall which have rusted or otherwise become damaged or deteriorated. Tube-wall sections are generally removed by using either hand held tools such as motor driven saws or cutting torches, or more desirably by using any of various track mounted cutting apparatuses. Hand held tools are generally undesirable, especially for removing more than a single tube from a tube-wall, because they tend to produce uneven cuts which make it difficult to weld a replacement tube-wall section onto the existing tube-wall. Track mounted cutting apparatuses such as those disclosed in U.S. Pat. No. 5,033,347 are preferred when relatively large sections of tube-wall, such as sections more than 3 feet in length, are to be removed. Conventional track mounted boiler cutting apparatus are however, relatively heavy, bulky and awkward, and require a relatively substantial amount of time and labor for installation and set-up. Accordingly, such track mounted apparatuses are not ideally suited for removing relatively short sections of boiler tube-wall.
A portable tube cutting apparatus having a vice-like fastener for supporting the apparatus from a stationary object, such as the tube which is to be cut, is disclosed in U.S. Pat. No. 5,199,221. The disclosed apparatus can be used to cut the tube which supports the apparatus as well as other adjacent tubes in close proximity. The device however is not generally suitable for cutting along a section of tube-wall wherein the individual tubes are continuously connected to an adjacent tube by a membrane, and wherein the tubes are generally too closely spaced to one another to permit use of the vice-like fastener for supporting the cutting apparatus on one of the tubes.
Accordingly, it would be highly desirable to provide a tube cutting apparatus which is lighter, more portable, and easier to install and set up than conventional track mounted cutting apparatuses, and which can be quickly and stably fastened to a tube-wall to allow a smooth even cut. Such apparatus would be particularly desirably in those situations where a relatively short section of tube-wall is to be removed, such as less than about 3 feet of tube-wall.